Path: utzoo!utgpu!jarvis.csri.toronto.edu!mailrus!tut.cis.ohio-state.edu!cs.utexas.edu!uunet!lll-winken!oli-stl!asylum!hoptoad!gnu
From: gnu@hoptoad.uucp (John Gilmore)
Newsgroups: gnu.gcc
Subject: Re: adding environment variables to gcc.c for pass/file locations
Message-ID: <7434@hoptoad.uucp>
Date: 26 May 89 01:57:31 GMT
References: <4463@omepd.UUCP> <5200@garfield.MUN.EDU>
Organization: Grasshopper Group in San Francisco
Lines: 21

I don't understand why people are proposing complicated additions to the
'gcc' driver program for this.  The existing facilities handle it quite
well.

If you want a variant of "gcc" that overrides the include files,
locations of passes, libraries, etc, just create a tiny shell script,
that does something like:

exec gcc -B/wherever -nostdlib -nostdinc -I. -I- -I/wherever/include \
	/somewhere/crt0.o $* /somewhere/lib/libc.a

This will handle 99% of the problem (I think the only catch is profiled
crt0's).  I used this to build 4.3BSD Unix with gcc (on a machine whose
libraries & include files didn't match my source tree).

The recent gcc feature that warns about unused arguments may thwart this
approach -- in that case we need a way to turn that warning off.
-- 
John Gilmore    {sun,pacbell,uunet,pyramid,amdahl}!hoptoad!gnu    gnu@toad.com
  A well-regulated militia, being necessary to the security of a free State,
  the right of the people to keep and bear arms, shall not be infringed.